Lower Sesan 2 Dam

Located near the confluence of the Sesan and Srepok rivers in Stung Treng province, Cambodia, the Lower Sesan 2 Dam threatens the vitality and biodiversity of two of the Mekong River’s most significant tributaries.

If built, the 400 MW project will have a costly catastrophic impact on the Mekong River’s fisheries and biodiversity. A 2012 study by the Proceedings of the National Academy of Sciences found that the Lower Sesan 2 Dam would cause a 9.3 percent drop in fish stocks basin-wide, while threatening more than fifty fish species. These impacts would be felt as far downstream as the Mekong Delta in Vietnam - the rice bowl of the country - and as far upstream as Laos and Thailand. Experts have also warned that the Lower Sesan 2 Dam will contribute to the changing of the Mekong’s hydrological flows, as well as a reduction of sediment flows by approximately six to eight percent.

Approximately five thousand people, many of whom are ethnic minorities, will be forcibly evicted to make way for the dam’s 33,560 hectare reservoir. The project will also forever alter the livelihoods and cultures of tens of thousands of people living along the Sesan and Srepok rivers, whose lives and traditions are closely linked to the river system and its rich natural resources. As people who have already experienced the adverse downstream impacts of Vietnam’s hydropower dams for more than a decade, communities living along the Sesan and Srepok rivers have been voicing their opposition to project for more than five years.

The $816 million project to be implemented by Hydropower Lower Sesan 2 Co., Ltd. is a joint venture between Cambodia’s Royal Group and Hydrolancang International Energy Co., Ltd (90%)and EVN International Joint Stock Company, a subsidiary of the Electricity of Vietnam (EVN) (10%). Financing for the project will come from the company's capital (30%) and an undisclosed bank loan (70%). The economic viability of this project has also been called into question, especially in light of increased droughts due to climate change and upstream dam operations.

Clearing for the dam's reservior began in March 2013 by Cambodia's Ang & Associates Lawyer Ltd. (a company owned by Royal Group's Kith Meng). The logging was halted in October 2013 and a commission of inquiry was established to investigate the operations of Ang & Associates, after repeated allegations of logging occuring outside of the concession area. Shorly after the call for a halt to logging, there were reports from villagers in the area that logging has continued. Since 2014, construction towards the dam has been underway, with a floating bridge constructed across the Sesan River, access roads built, as well as signs that an embankment wall or coffer dam is being built.

In June 2013 and 2014, international donors, including the governments of Australia, Finland, Japan and the USA, called upon Cambodia to voluntarily submit the Lower Sesan 2 Dam to the Mekong River Commission's 'prior consultion' process, which would allow for regional decision-making given the dam's expected transboundary impacts. Cambodia has yet to respond to these requests.

International Rivers has heard reports in 2014 that Hydrolancang has resdesigned the Lower Sesan 2 Dam with significant changes towards structure and the height of the dam and urges the Cambodian government to halt the dam's construction, put the new design into the public dominan, while also carrying out a new environmental impact assessment, which also considers transboundary impacts, before a decision is made over whether construction should proceed.

International Rivers is working with partners in Cambodia calling upon the government of Cambodia to cancel this project. With such significant environmental, social and economic costs, the Lower Sesan 2 Dam is clearly the wrong solution for the region’s energy and water needs.

Watch the film Hydropower in the Mekong Basin: Impacts and Alternatives questioning "How can sustainable energy be developed, while avoiding the associated negative impacts that dams can cause to food security and vital ecosystem services for the people of Cambodia?" released on 14 November 2013.